City's consumers urged to support only sustainable fishing Hong Kong's huge demand for fish, often obtained by using unsustainable methods such as cyanide fishing, has destroyed the natural habitat for coral and fish in Indonesia and the Philippines, a coral reef expert said yesterday. Thomas Goreau, president of the Global Coral Reef Alliance, a non-profit organisation dedicated to the protection of coral reefs, urged Hong Kong to support fishing in countries that use sustainable methods. 'Hong Kong is a major market for fisheries products. Almost all the fish supplied to Hong Kong is caught by cyanide fishing. The Hong Kong market has destroyed [the natural habitat for corals] in Indonesia and the Philippines,' Dr Goreau said. 'You can stop the fishing but the fish will not come back if there is no coral or habitat for them.' Dr Goreau is due to fly to the Philippines, from where he has helped local communities restore their shoreline through a process called Biorock, invented by colleague Wolf Hilbertz. The Biorock process involves inserting steel frames into the seabed and charging them with a low-voltage electrical current to prevent the steel from rusting. Over time, the rods attract minerals in the water to grow limestone. Coral can also be grown using the same method and Dr Goreau said he had helped many communities restore their coral reefs and shorelines using this method. He said the process could be fuelled by solar power, chargers, batteries or even waves. 'The corals [grown using the Biorock process] grow three to five times faster and heal 20 times faster,' Dr Goreau said. Some of his projects had shown that corals grown this way were 95 per cent more resilient. Global warming was the main coral killer worldwide. Dr Goreau said most of the areas where coral was found, including Hainan , had experienced a one to two degree Celsius increase in temperature since 1982. 'In the last 10 years we have lost almost all of the world's coral. The Maldives lost 90 per cent of its coral in 1998, and in Palau in 1998, most of the coral died within a few weeks,' Dr Goreau said. 'We only have reefs. Not all the reefs are gone but they will disappear eventually.' Other major sources of destruction are diseases, land-based sources of pollution such as sewage and fertiliser and human activity. 'We are already most of the way through the first mass destruction of corals,' he said. But Dr Goreau warned that keeping corals alive would not be easy because all sources of destructive activity had to be addressed simultaneously. He said Hong Kong was only a marginal area for corals because Pearl River pollution made it unfavourable for corals, which thrive in clear water. But the Biorock process can also be used to grow habitats for lobsters and other sea creatures that inhabit spaces under rocks.